The email type runs off the communication preference field, that lives at the contacts object in OnePlace.
You will need to add the extra values against that field in OnePlace.
Then reach out to your CSM, to let them know the new email types as they will need to update the fields in the CRM meta data tool, and whether or not these email types should be added to an unsubscribe page.
For more information on Intapp OnePlace Emails, see this article.